跨导放大器

200 mA to 100A in six ranges
* over range capability
40ppm short term stability
0.04% dc and 0.10% ac accuracy
Accuracy independent of load
Distortion below -60dB
Complete Front Panel Calibration
IEEE-488.2 Interface standard
Stable with inductive loads
High output impedance
Power Factor corrected supplies
      （PF>0.98 at 100A output）

WIDE CURRENT RANGE / EXTREMELY BROADBAND
The Model 8100 Transconductance Amplifier is a precision, high stability, high accuracy instrument which produces an output current which is directly proportional to the input voltage over the frequency range from dc to 100kHz. Six overlapping ranges, with full scale values of 2mA, 20mA, 0.2A, 2A, 20A and 100A, provide low distortion output currents from 200uA to 100A. With the exception of the 100A range, for which a 1 V rms input produces the 100 Arms output current, the transconductance of the other ranges is set such that a 2Vrms input produces the full scale output current. With the exception of the 100A range, all of the other ranges may be operated to twice their full scale value without any deterioration in performance.

LOW TOTAL HARMONIC DISTORTION
The total harmonic distortion introduced by the transconductance amplifier is less than -60dB up to 10 kHz （typically 20kHz） and less than -40dB to 100kHz for all current ranges.

AMPLE COMPLIANCE VOLTAGE
The maximum compliance voltage （the maximum permissible voltage which can be developed across a load connected across the output） is at least 7Vrms （7V for dc） for all ranges and all frequencies. This high voltage limit permits a large variety of loads to be driven from the transconductance amplifier. These loads may be resistive or resistive with capacitive or inductive components without causing any instability in the output current. An OVERCOMPLIANCE indicator is illuminated when the 7V has been exceeded.

FREQUENCY AND COMPLIANCE VOLTAGE DISPLAYED
Both the compliance voltage （0.00V - 7.00V） and the frequency of the input voltage drive （10Hz - 500kHz） are continuously displayed by bright seven-segment LED displays.

HIGHER FREQUENCY OUTPUTS AVAILABLE
With the exception of the 20A range and the 100A range which are internally limited to 110kHz, the Model 8100 Transconductance Amplifier will normally supply full scale currents up to at least 500kHz into suitable loads.

WIDE RANGE OF APPLICATIONS
The Model 8100 Transconductance Amplifier is ideally suited for calibration of any device that requires a precision current excitation. High current and high frequency combinations are available that have heretofore been difficult to obtain. The Model 8100 may be used to calibrate （or to develop） current transformers, shunts, ammeters and V-A-W meters. Whenever the compliance voltage limits will allow it, units may be paralleled to obtain even higher currents.

EASY TO CALIBRATE
The Model 8100 Transconductance Amplifier has a CALIBRATION PANEL on the front panel which allows the unit to be calibrated without having to remove either the top or bottom cover. The Calibration Mode is activated by breaking the seal over the CAL key and then depressing it with a small, narrow screwdriver. When the CAL key is again depressed, the new calibration points are stored in an internal non-volatile memory.

COAXIAL OUTPUT FOR HIGH CURRENTS
To minimize the output inductance, the current output for both the 20A and the 100A range is supplied through a coaxial LC connector. The output current for the lower current ranges, where inductance is not as much of a problem, is supplied through a set of recessed safety terminals.

IEEE-488.2 BUS CONTROL
The Model 8100 Transconductance Amplifier is equipped with an IEEE-488.2 interface which incorporates all of the common commands and queries. Any function which can be entered manually can be sent by a bus controller to the Transconductance Amplifier over the IEEE interface. In addition, the frequency and the compliance voltage, which are displayed on the front panel, can be queried by the controller and returned to it over the bus. The status and states （e.g. current range, standby, etc.） of the Transconductance Amplifier can also be queried by the controller and returned over the bus. The bus address is set from the front panel and is displayed both at turn on and when the LOCAL key is pressed. A REMOTE lamp indicates that the Model 8100 has been placed in its Remote state by the controller.

SPECIFICATIONS

COMPLIANCE VOLTAGE  

INDUCTIVE LOADS   

DISPLAYS

IEEE-488.2 INTERFACE SUBSETS  

  SH1, AH1, T6, L4, SR1, RL1, PP0, DT0, DC1